The spot size converter based on the
arrayed waveguide grating and the
waveguide type
detector adopts a double-step type
waveguide structure comprising a first
waveguide and a second waveguide, the first waveguide and the second waveguide are both of reverse conical waveguide structures, and the transition mode of the first waveguide and the second waveguide is parabola type transition; the large end face of the first waveguide is aligned with the large end face of the second waveguide, the large end face of the first waveguide is an incident face of output light of the array
waveguide grating, the small end face of the second waveguide is a light emitting face, and light originally limited in a core layer of the first waveguide is coupled into a core layer of the second waveguide, so that a mode field is reduced, and the light emitting efficiency is improved. A mode field in the array
waveguide grating is converted into a mode field in the
ridge waveguide of the waveguide type
detector, and matching of the array
waveguide grating and the mode field of the waveguide type
detector is achieved. The end face
coupling mode is adopted, the
light field is coupled into the absorption area from the side face, loss and scattering of the
light field in the waveguide propagation process are reduced, the light
coupling efficiency is further improved, and integrated application of the photoelectric detector is facilitated.